Abstract: A heat source unit includes a compressor, a heat source heat exchanger, a first shutoff valve, a second shutoff valve, a refrigerant flow path, and a refrigerant. The refrigerant flow path is a flow path in which the compressor, the heat source heat exchanger, the first shutoff valve, and the second shutoff valve are connected by a refrigerant pipe. The refrigerant flow path is filled with the refrigerant. The refrigerant includes carbon dioxide. A filling amount V1 (kg) of the refrigerant filled in the refrigerant flow path, a volume V2 (L) of the refrigerant flow path, and a design pressure P (MPa) of the refrigerant flow path satisfy the following relationship. V1×a?V2?V1×b, a=0.078×P2?2.111×P+15.771, and b=0.055 ×P2?1.768×P+16.144.

Abstract: In a refrigeration cycle apparatus, a switching mechanism includes a first channel and performs switching among a first, second and third connection states. In the first connection state, the refrigeration cycle apparatus repeatedly performs a first cycle in which refrigerant flows through a compressor, a first heat exchanger, a second heat exchanger, and the compressor in that order. In the second connection state, the refrigeration cycle apparatus repeatedly performs a second cycle in which refrigerant flows through the compressor, the second heat exchanger, the first heat exchanger, and the compressor in that order. In the third connection state, a passage between the compressor and the first heat exchanger and a passage between the compressor and the second heat exchanger are closed, and the first channel in the refrigeration cycle apparatus provides interconnection between the first heat exchanger and the second heat exchanger.

Abstract: The ventilation system 1 according to the present disclosure includes: a refrigerant circuit 60; an air supply path having an interior in which a first heat exchanger 12 and a first air supply fan 22A and a second air supply fan 22B are arranged; an exhaust air path having an interior in which a second heat exchanger 32 and an exhaust fan 42 are arranged; a first air supply detector 23A for detecting a first supply airflow AF1 blown out by the first air supply fan 22A; a second air supply detector 23B for detecting a second supply airflow AF2 blown out by the second air supply fan 22B; and a control unit CU. The control unit CU executes first air supply control to adjust the rotational speed of the first air supply fan 22A so that the first supply airflow AF1 becomes a target value TV1, and second air supply control to adjust the rotational speed of the second air supply fan 22B so that the second supply airflow AF2 becomes a target value TV2.

Abstract: A refrigerant cycle system includes: a first refrigerant circuit that includes a first heat exchanger, a first compressor, and a first cascade heat exchanger and that is configured as a first vapor compression refrigeration cycle; a second refrigerant circuit that includes the first cascade heat exchanger, a second compressor, and a second heat exchanger and that is configured as a second vapor compression refrigeration cycle; a first unit that accommodates the first heat exchanger and the first compressor; a second unit that accommodates the first cascade heat exchanger and the second compressor; and a third unit that accommodates the second heat exchanger. The first unit, the second unit, and the third unit are disposed apart from each other. The first cascade heat exchanger performs heat exchange between a first refrigerant that flows through the first refrigerant circuit and a second refrigerant that flows through the second refrigerant circuit.

Abstract: At a refrigeration cycle device, an injection pipe and an economizer heat exchanger are provided at a main refrigerant circuit. In addition, the refrigeration cycle device includes a sub-refrigerant circuit having a sub-usage-side heat exchanger. At the refrigeration cycle device, the sub-usage-side heat exchanger functions as an evaporator of a sub-refrigerant and cools a main refrigerant that has been cooled at the economizer heat exchanger, or functions as a radiator of the sub-refrigerant and heats the main refrigerant that has been cooled at the economizer heat exchanger.

Abstract: Even if, in decompressing a refrigerant by an expansion mechanism, the temperature of the refrigerant cannot be sufficiently reduced, in order to increase the evaporation capacity of a use-side heat exchanger, a main expansion mechanism including an expansion element of a rotary or scroll type that causes power to be produced by decompressing a main refrigerant is provided at a main refrigerant circuit in which the main refrigerant circulates. Further, a sub-refrigerant circuit that differs from the main refrigerant circuit and in which a sub-refrigerant circulates is provided. A sub-use-side heat exchanger that is provided at the sub-refrigerant circuit and that functions as an evaporator of the sub-refrigerant is caused to function as a heat exchanger that cools the main refrigerant that flows between the main expansion mechanism and a main use-side heat exchanger.

Abstract: A refrigeration cycle device that includes a main refrigerant circuit and a sub-refrigerant circuit cools or heats a main refrigerant that flows between a main heat-source-side heat exchanger and a main usage-side heat exchanger by causing a sub-usage-side heat exchanger to function as an evaporator or a radiator of a sub-refrigerant. A first main expansion mechanism and a second main expansion mechanism that decompress the main refrigerant are provided on an upstream side and a downstream side of the sub-usage-side heat exchanger of the main refrigerant circuit.

Abstract: A suction injection pipe and a subcooling heat exchanger are provided at a main refrigerant circuit in which a main refrigerant circulates. Further, a sub-refrigerant circuit that differs from the main refrigerant circuit and in which a sub-refrigerant circulates is provided. A controller performs control for switching between a cooling action of the subcooling heat-exchanger that cools the main refrigerant that is sent to a main use-side heat exchanger by using the suction injection pipe and the subcooling heat exchanger, and a cooling action of the sub-refrigerant-circuit that cools the main refrigerant that is sent to the main use-side heat exchanger by using the sub-refrigerant circuit.

Abstract: A heat transport system includes: a refrigerant circuit that seals therein a fluid including HFC-32 and/or HFO refrigerant as a refrigerant and that includes a refrigerant booster that boosts the refrigerant, an outdoor air heat exchanger that exchanges heat between the refrigerant and outdoor air, a medium heat exchanger that exchanges heat between the refrigerant and a heat transfer medium, and a refrigerant flow path switch that switches between a refrigerant radiation state and a refrigerant evaporation state; and a medium circuit that seals carbon dioxide therein as the heat transfer medium.

Abstract: A refrigeration cycle device includes a heat source, a first use unit, a second use unit, a first connection flow path, and a second connection flow path. The heat source has a compressor and a heat-source side heat exchanger. The first use unit is separated from the heat source unit and has a first use-side heat exchanger. The second use unit is separated from the heat source unit and has a second use-side heat exchanger. The first connection flow path connects the heat source unit to the first and the second use units and causes a first refrigerant to flow. The second connection flow path connects the heat source unit to the first and the second use units and causes a second refrigerant to flow. A specific enthalpy of the second refrigerant is smaller than a specific enthalpy of the first refrigerant.

Abstract: A drainage mechanism is connected to a drain pump that sucks water from a drain pan. The drainage mechanism includes a connecting part that connects to the drain pump, a first flow path, a folded part, and a second flow path. The first flow path extends upward from the connecting part. The folded part has a first end connected to an upper end of the first flow path and a second end on a side opposite to the first end. The folded part changes a direction of the water flowing therein from upward to downward. The second flow path extends from the second end. The second flow path is a pipe that has an inner diameter of 13 mm or less. The flow path area of the folded part is larger than the flow path area of the second flow path.

Abstract: A refrigerant cycle system includes: a first refrigerant circuit that includes a first heat exchanger, a first compressor, and a first cascade heat exchanger and that is configured as a first vapor compression refrigeration cycle; a second refrigerant circuit that includes the first cascade heat exchanger, a second compressor, and a second heat exchanger and that is configured as a second vapor compression refrigeration cycle; a first unit that accommodates the first heat exchanger and the first compressor; a second unit that accommodates the first cascade heat exchanger and the second compressor; and a third unit that accommodates the second heat exchanger. The first unit, the second unit, and the third unit are disposed apart from each other. The first cascade heat exchanger performs heat exchange between a first refrigerant that flows through the first refrigerant circuit and a second refrigerant that flows through the second refrigerant circuit.

Abstract: A refrigeration cycle device includes a heat source, a first use unit, a second use unit, a first connection flow path, and a second connection flow path. The heat source has a compressor and a heat-source side heat exchanger. The first use unit is separated from the heat source unit and has a first use-side heat exchanger. The second use unit is separated from the heat source unit and has a second use-side heat exchanger. The first connection flow path connects the heat source unit to the first and the second use units and causes a first refrigerant to flow. The second connection flow path connects the heat source unit to the first and the second use units and causes a second refrigerant to flow. A specific enthalpy of the second refrigerant is smaller than a specific enthalpy of the first refrigerant.

Abstract: In a refrigeration cycle apparatus, a switching mechanism includes a first channel and performs switching among a first, second and third connection states. In the first connection state, the refrigeration cycle apparatus repeatedly performs a first cycle in which refrigerant flows through a compressor, a first heat exchanger, a second heat exchanger, and the compressor in that order. In the second connection state, the refrigeration cycle apparatus repeatedly performs a second cycle in which refrigerant flows through the compressor, the second heat exchanger, the first heat exchanger, and the compressor in that order. In the third connection state, a passage between the compressor and the first heat exchanger and a passage between the compressor and the second heat exchanger are closed, and the first channel in the refrigeration cycle apparatus provides interconnection between the first heat exchanger and the second heat exchanger.

Abstract: A drainage mechanism is connected to a drain pump that sucks water from a drain pan. The drainage mechanism includes a connecting part that connects to the drain pump, a first flow path, a folded part, and a second flow path. The first flow path extends upward from the connecting part. The folded part has a first end connected to an upper end of the first flow path and a second end on a side opposite to the first end. The folded part changes a direction of the water flowing therein from upward to downward. The second flow path extends from the second end. The second flow path is a pipe that has an inner diameter of 13 mm or less. The flow path area of the folded part is larger than the flow path area of the second flow path.

Abstract: A heat transport system includes: a refrigerant circuit that seals therein a fluid including HFC-32 and/or HFO refrigerant as a refrigerant and that includes a refrigerant booster that boosts the refrigerant, an outdoor air heat exchanger that exchanges heat between the refrigerant and outdoor air, a medium heat exchanger that exchanges heat between the refrigerant and a heat transfer medium, and a refrigerant flow path switch that switches between a refrigerant radiation state and a refrigerant evaporation state; and a medium circuit that seals carbon dioxide therein as the heat transfer medium.

Abstract: A heat transport system includes: a refrigerant circuit that seals therein a fluid including HFC-32 and/or HFO refrigerant as a refrigerant and that includes: a refrigerant booster that boosts the refrigerant; an outdoor air heat exchanger that exchanges heat between the refrigerant and outdoor air; a medium heat exchanger that exchanges heat between the refrigerant and a heat transfer medium; and a refrigerant flow path switch that switches between a refrigerant radiation state and a refrigerant evaporation state; and a medium circuit that seals carbon dioxide therein as the heat transfer medium.

Abstract: In order to increase the evaporation capacity of a use-side heat exchanger regardless of operating conditions, a suction injection pipe and a subcooling heat exchanger are provided at a main refrigerant circuit in which a main refrigerant circulates. Further, a sub-refrigerant circuit that differs from the main refrigerant circuit and in which a sub-refrigerant circulates is provided. A controller performs control for switching between a cooling action of the subcooling heat-exchanger that cools the main refrigerant that is sent to a main use-side heat exchanger by using the suction injection pipe and the subcooling heat exchanger, and a cooling action of the sub-refrigerant-circuit that cools the main refrigerant that is sent to the main use-side heat exchanger by using the sub-refrigerant circuit 80.

Abstract: A refrigeration cycle device that includes a main refrigerant circuit and a sub-refrigerant circuit cools or heats a main refrigerant that flows between a main heat-source-side heat exchanger and a main usage-side heat exchanger by causing a sub-usage-side heat exchanger to function as an evaporator or a radiator of a sub-refrigerant. A first main expansion mechanism and a second main expansion mechanism that decompress the main refrigerant are provided on an upstream side and a downstream side of the sub-usage-side heat exchanger of the main refrigerant circuit.

Abstract: At a refrigeration cycle device, an injection pipe and an economizer heat exchanger are provided at a main refrigerant circuit. In addition, the refrigeration cycle device includes a sub-refrigerant circuit having a sub-usage-side heat exchanger. At the refrigeration cycle device, the sub-usage-side heat exchanger functions as an evaporator of a sub-refrigerant and cools a main refrigerant that has been cooled at the economizer heat exchanger, or functions as a radiator of the sub-refrigerant and heats the main refrigerant that has been cooled at the economizer heat exchanger.